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CRISPR is our genetic superweapon. Derived from the cellular machinery of bacteria, Scientists have already started using it to fight everything from cancer to HIV. This mostly works by snipping out little bits of genetic code and replacing it with special sequences meant to correct errors in our genetic code. While that’s pretty freaking sweet on its own, it may yet cure more mundane diseases without actually cutting or splicing genes at all.

In a new paper published in the journal Cell, researchers at the Salk Institute propose using CRISPR not to edit genes, but to turn them off and on instead.

This comes on the heels of some questions that have been raised about CRISPR’s safety. There are some studies that suggest the technique sometimes makes mistakes, causing unpredictable (and possibly dangerous) changes to the genetic code. So far, no major alarm bells have gone off, and CRISPR has had plenty of successes, but when we’re mucking with the very code that makes us, it’s important to be safe about it.

“The recent revolution in targeted gene-editing technologies has opened a new door for targeted precision medicine,” the study’s co-authors, Fumiyuki Hatanaka and Hsin-Kai Liao, told Gizmodo. “However, generating double-strand breaks has the risk of causing permanent, unwanted mutations. This concern is a hurdle to using CRISPR to treat humans.”

This new technique leverages an evolving understanding of how the genomes work. For some time, a lot of emphasis was placed on the raw genetic code. That is, the letters representing base pairs that your cells read and use to make proteins. More recently, however, studies have focused on the effects of more complex pieces of the DNA as a whole molecule — how tightly it’s wound, whether genes are turned on or off at any given point and why.

This is particularly helpful, because, as noted above, genes can be flipped much like switches. You don’t need to cut them out, necessarily. And cutting is risky — like with any machine, the more steps you introduce, the more things can go wrong. When CRISPR goes to work, it cuts through both strands of DNA, too, meaning that you need to be damned sure that you’re putting the right code back in, or you could end up with random gibberish in a critical spot. And that could mean that you die. Or get cancer. Or get cancer and die.

Hatanaka and Liao’s method drops the snip-snip part of the procedure, and it’s already successfully been used on mice with diabetes, renal disease, and muscular dystrophy. All it took was flipping certain codes on or off as needed, and within short order, the test subjects improved dramatically.

It’s a start, but a promising one that could yield dividends down the line. The entire field of genome editing is moving along at dizzying speed, and there’s strong potential in many of the techniques and tools researchers are developing now to cure many of humanity’s most pernicious diseases and potentially even stop aging or engineer totally new super-humans. We are indeed living in interesting times.